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03-10-2011, 03:55 PM   #331
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Having taken a few dozen test shots around the house in dim light with my Sigma 30mm at f/1.4, I have to say I'm *very* pleased with Firmware V1.03.

03-10-2011, 06:02 PM   #332
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QuoteOriginally posted by Class A Quote
You should have clarified (as you did in another post) that you allowed the AF assist to come on in some occasions.
Thanks - I probably should have.

I think the AF assist was engaged for most of the shots (including both those that FF and those that were fine) - hence even using the AF assist the camera still misfocuses.

This is an apparent behaviour change from the factory firmware - the AF assist is much more likely to turn on than the factory firmware.
03-10-2011, 06:39 PM   #333
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QuoteOriginally posted by glanglois Quote
We need a new forum: Falk Lumo Reports. Saves your valuable time.
And a PayPal button so we can donate a Pentax logo custom seat cover for his Audi.
03-11-2011, 01:44 AM   #334
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QuoteOriginally posted by Aristophanes Quote
And a PayPal button so we can donate a Pentax logo custom seat cover for his Audi.
He drives an Audi? Guy's got taste

03-11-2011, 05:53 AM   #335
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QuoteOriginally posted by Erik Quote
He drives an Audi? Guy's got taste
Guy's is German, IIRC, so Audi, BMW, or VW were pretty much mandatory

Same thing for me : Peugeot and Renault (mmmmh, only this does not sound so cool )
03-11-2011, 12:29 PM   #336
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QuoteOriginally posted by dlacouture Quote
Guy's is German, IIRC, so Audi, BMW, or VW were pretty much mandatory

Same thing for me : Peugeot and Renault (mmmmh, only this does not sound so cool )
you could always go with Citroen, they ain't so bad

NaCl(they do pretty good in the World Rally Championship)H2O
03-11-2011, 04:26 PM   #337
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QuoteOriginally posted by dlacouture Quote
Same thing for me : Peugeot and Renault (mmmmh, only this does not sound so cool )
Bah, I wouldn't trade our Peugeot for an Audi
03-12-2011, 02:25 AM   #338
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QuoteOriginally posted by NaClH2O Quote
you could always go with Citroen, they ain't so bad
Man, I'd love a C6, those "hydractive" pneumatic shock absorbers are pure bliss...

03-13-2011, 05:34 PM   #339
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QuoteOriginally posted by Class A Quote
Do you think it might perhaps be good to get some data with the old firmware regarding the potential peak of defocus around EV 8?
I will not evaluate the EV6-8 region in this context. If the problem persists, it may become a separate topic. Currently, I live under the assumption that a mismatch of color at the AF point and globally, may have caused issues around that EV range. I'll include a look at this "color mismatch" in my updated paper, although at lower EV.

I've already done all test shots and now need to run the analysis and write it up.
03-13-2011, 06:43 PM   #340
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Hi Falk,

QuoteOriginally posted by falconeye Quote
I will not evaluate the EV6-8 region in this context.
Fair enough, I fully understand. I just thought I mention the problem before you update the firmware as there is probably no straightforward way of reverting to an older version (that doesn't involve hacking the old firmware to pretend it isn't older).

QuoteOriginally posted by falconeye Quote
I've already done all test shots and now need to run the analysis and write it up.
Great! My gut feeling is that while some improvement has been achieved there is still a residual problem. So probably one, rather than two thumbs up.
03-13-2011, 06:46 PM   #341
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QuoteOriginally posted by NaClH2O Quote
you could always go with Citroen, they ain't so bad
CitroŽns are funtastic (sic).
03-17-2011, 02:13 PM   #342
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tomtomtomtomtomtomtomtomtomtomtom...
as in Jaws..sort of...eh.
03-17-2011, 05:59 PM   #343
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Intermediate update for firmware 1.03

Hi friends,

I am through the analysis of the v1.03 data and I am a bit confused. Maybe, somebody can help before I write my update.

According to my measurements, v1.03 brings no significant progress IF the following conditions are met:

1. The FA 31 lens is used at 1m distance and f/1.8 aperture.
2. The background is bright.
3. The camera white balance is manually set to daylight (maybe doesn't matter).
4. The light color is tungsten (maybe doesn't matter).

Wrt (3.), I see some positive effect if the camera white balance is set to automatic or tungsten. However, I don't have enough data points (I have 21 measurements for this case) to call this effect significant, i.e., these 21 data points all lie within the cloud of 94 data points obtained with daylight white balance. I even see some negative effect of v1.03 if the subject has a red color and the lamp has not.

OTOH, I trust the numerous positive reports and I must assume that I must miss this effect for some reason.

Maybe, the white balance effect is significant. Maybe, the effect is only noticeable with lenses slower than f/1.8. Or maybe, only at higher EV values with darker backgrounds.

Unfortunately, I am far away from my lab and can't do further measurements for the next three weeks.


Is there anybody wanting to check if the positive v1.03 effect disappears with a wide aperture and/or a non-matching camera white balance?


Thanks everybody.
03-17-2011, 08:20 PM   #344
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QuoteOriginally posted by falconeye Quote
Hi friends,

I am through the analysis of the v1.03 data and I am a bit confused. Maybe, somebody can help before I write my update.

According to my measurements, v1.03 brings no significant progress IF the following conditions are met:

1. The FA 31 lens is used at 1m distance and f/1.8 aperture.
2. The background is bright.
3. The camera white balance is manually set to daylight (maybe doesn't matter).
4. The light color is tungsten (maybe doesn't matter).

Wrt (3.), I see some positive effect if the camera white balance is set to automatic or tungsten. However, I don't have enough data points (I have 21 measurements for this case) to call this effect significant, i.e., these 21 data points all lie within the cloud of 94 data points obtained with daylight white balance. I even see some negative effect of v1.03 if the subject has a red color and the lamp has not.

OTOH, I trust the numerous positive reports and I must assume that I must miss this effect for some reason.

Maybe, the white balance effect is significant. Maybe, the effect is only noticeable with lenses slower than f/1.8. Or maybe, only at higher EV values with darker backgrounds.

Unfortunately, I am far away from my lab and can't do further measurements for the next three weeks.


Is there anybody wanting to check if the positive v1.03 effect disappears with a wide aperture and/or a non-matching camera white balance?


Thanks everybody.
first of thanks for all the hard work.

I have got to admit to not having read you paper fully yet.

Talking lenses in the F2.0 and below range, I have tested with the FA*24, FA43ltd and FA77, the 24 and77 were pretty accurate already before 1.0.3, but 1.0.3 has really improved on the 43, so now all of them are spot on, with only an occasional miss.

Is it possible that the reason you are not seeing an improvement could be an issue with your specific lens/body combination?
03-17-2011, 08:21 PM   #345
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Hi Falks, thanks for the update.

QuoteOriginally posted by falconeye Quote
According to my measurements, v1.03 brings no significant progress IF the following conditions are met:
Wow, that's bad news. Even in the conditions you list, AFAIC, there shouldn't be such a discontinuous jump in the choice of focus plane. Unless the colorimetric sensor really has such a sharp transition to blindness, a discontinuous behaviour would still point to a firmware bug (or a limitation of a correction table size).

Is your set of criteria a positive list only? In other words, I guess that I cannot conclude from it that there is a significant improvement if the background is not bright, right?

QuoteOriginally posted by falconeye Quote
Wrt (3.), I see some positive effect if the camera white balance is set to automatic or tungsten.
Oh dear, would be a shame if the K-5 were relegated to K-r tricks... (I know that this effect is not confirmed but it seems that this would be a reasonable step to take in cases where the colorimetric sensor isn't useful anymore).

QuoteOriginally posted by falconeye Quote
Maybe, the effect is only noticeable with lenses slower than f/1.8.
Ray Pulley has posted test shots that show a significant change to the focus plane when using an FA 50/1.4 at EV 2 (<- Sekonic L-358 reading at focus target).

To be honest, overall, that's quite disappointing news...
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